In a typical dual-diversity troposcatter link the desired signal is received on two high gain (typically 38 to 40 dB gain) antennas. The amplitudes of these signals exhibit independent fading, and a diversity combiner forms an output that exhibits loss of SNR less frequently than on either antenna separately. The average troposcatter signal strength is always quite weak, however, and it is possible for a jammer within line-of-sight of the antennas to produce interference through the sidelobes of the antennas even though the sidelobe gain of the antennas is typically at least 20 dB lower than the main lobe gain.
The purpose of the present invention is to provide sidelobe jamming suppression in troposcatter sets of this type and to do so with an implementation that is applicable to all tactical and strategic troposcatter receiving terminals. The invention avoids the accidental suppression of the desired signal during quiet intervals of intermittent jamming even in the presence of signal fading whereas conventional sidelobe cancellers are suitable only for use with steady jamming and constant strength of desired signal.